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Using iMapInvasives to Inventory Weeds

in the Columbia River Gorge


The Columbia River Gorge draws thousands of visitors a year for hiking, fishing, boating, bird watching, wind surfing, and many other activities. Along with stunning views and dramatic geology, visitors can see a variety of wildlife and wildflowers in the Gorge, but unfortunately many of the blooming species they see while enjoying this National Scenic Area are unwelcome weeds. Some species in particular have been targeted for early detection efforts, to help prevent their spread before they can become too established here. 

As the largest river in the Pacific Northwest, the Columbia River is an important transportation corridor for people, commerce, wildlife, and for spreading invasive species. How best to monitor a mix of state, federal, and private lands in two states separated by a river that can be miles across? Cooperative weed management groups on both sides of the river have banded together to form the Columbia River Gorge Cooperative Weed Management Area (CG-CWMA). The group includes representatives of several agencies, non-profits, and universities who work together to protect the Gorge from invasive species. 

Columbia River Gorge, Oregon and Washington States.

Photo by Jan Tik, Wikimedia Commons.

In 2011 and 2012, funding was secured by the National Fish and Wildlife Foundation (NFWF) to gather existing invasive species data, perform new surveys, and launch an early detection, rapid response campaign to engage visitors. The CG-CWMA decided to use the iMapInvasives platform for sharing observation and treatment data collected during the project. As an open source, online platform, all project members and the interested public would gain access to the data collected during the project. To make field collection easier, an ArcPad tool developed by the Florida Natural Areas Inventory for use with iMapInvasives was adapted for the project. Team members could then use portable GIS units to draw observations and survey polygons while in the field, and use the ArcPad program to collect data that could easily be imported into the iMapInvasives program. 

Emily Stevenson maps invasive species on the river using an ArcPad program with iMapInvasives data fields. 

Photo by Columbia River Gorge CWMA.

Armed with weather resistant gear and clothing, project leader Emily Stevenson spent two summers traveling throughout the Gorge by boat, car, and on foot to seek out locations of early invaders and established weed patches including false brome (Brachypodium sylvaticum), garlic mustard (Alliaria petiolata), and knotweed (Polygonum spp.). Several hundred new observations were made in addition to collecting existing data. Using the iMapInvasives platform allowed all these different data types to be reformatted into a standardized dataset accessible online. The project was a huge success, even attaining a television spot on the Oregon Public Broadcasting show Oregon Field Guide. Now that the CG-CWMA has baseline data as well as new observations and survey results, the team can better prioritize future treatment and survey efforts and can easily share data between all partners. The early detection campaign installed several boot brush stations at twenty-five popular trailheads and posted signs to alert visitors to the threat of invasive species, increasing awareness in this popular and well-traveled scenic area. Visitors can report invasive species sightings by calling an invasive species hotline, or can use their smart phones to report observations directly to iMapInvasives. Engaging both land managers and visitors to the Gorge will ensure the protection of its natural beauty and biodiversity for generations to come. 


As one of the largest conservation funders in the world, NFWF supports hundreds of science-based, results-oriented projects that bring new solutions to the country’s biggest conservation challenges. Across the U.S., NFWF funds projects to save imperiled species, promote healthy coasts, forests and grasslands, and guarantee

water for wildlife and people. With federal, state and local agencies and corporate partners, NFWF finds common ground between the public and private sectors to achieve positive conservation results. 

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